freebsd-dev/sys/arm64/qualcomm/qcom_gcc.c
Ruslan Bukin 5819c3eb8a Enable Qualcomm Debug Subsystem (QDSS) block on MSM8916 SoC.
This is required for ARM Coresight operation on Dragonboard 410c.

Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D14987
2018-04-10 12:53:48 +00:00

149 lines
4.2 KiB
C

/*-
* Copyright (c) 2018 Ruslan Bukin <br@bsdpad.com>
* All rights reserved.
*
* This software was developed by BAE Systems, the University of Cambridge
* Computer Laboratory, and Memorial University under DARPA/AFRL contract
* FA8650-15-C-7558 ("CADETS"), as part of the DARPA Transparent Computing
* (TC) research program.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/kthread.h>
#include <sys/rman.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <machine/bus.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>
#define GCC_QDSS_BCR 0x29000
#define GCC_QDSS_BCR_BLK_ARES (1 << 0) /* Async software reset. */
#define GCC_QDSS_CFG_AHB_CBCR 0x29008
#define AHB_CBCR_CLK_ENABLE (1 << 0) /* AHB clk branch ctrl */
#define GCC_QDSS_ETR_USB_CBCR 0x29028
#define ETR_USB_CBCR_CLK_ENABLE (1 << 0) /* ETR USB clk branch ctrl */
#define GCC_QDSS_DAP_CBCR 0x29084
#define DAP_CBCR_CLK_ENABLE (1 << 0) /* DAP clk branch ctrl */
static struct ofw_compat_data compat_data[] = {
{ "qcom,gcc-msm8916", 1 },
{ NULL, 0 }
};
struct qcom_gcc_softc {
struct resource *res;
};
static struct resource_spec qcom_gcc_spec[] = {
{ SYS_RES_MEMORY, 0, RF_ACTIVE },
{ -1, 0 }
};
/*
* Qualcomm Debug Subsystem (QDSS)
* block enabling routine.
*/
static void
qcom_qdss_enable(struct qcom_gcc_softc *sc)
{
/* Put QDSS block to reset */
bus_write_4(sc->res, GCC_QDSS_BCR, GCC_QDSS_BCR_BLK_ARES);
/* Enable AHB clock branch */
bus_write_4(sc->res, GCC_QDSS_CFG_AHB_CBCR, AHB_CBCR_CLK_ENABLE);
/* Enable DAP clock branch */
bus_write_4(sc->res, GCC_QDSS_DAP_CBCR, DAP_CBCR_CLK_ENABLE);
/* Enable ETR USB clock branch */
bus_write_4(sc->res, GCC_QDSS_ETR_USB_CBCR, ETR_USB_CBCR_CLK_ENABLE);
/* Out of reset */
bus_write_4(sc->res, GCC_QDSS_BCR, 0);
}
static int
qcom_gcc_probe(device_t dev)
{
if (!ofw_bus_status_okay(dev))
return (ENXIO);
if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
return (ENXIO);
device_set_desc(dev, "Qualcomm Global Clock Controller");
return (BUS_PROBE_DEFAULT);
}
static int
qcom_gcc_attach(device_t dev)
{
struct qcom_gcc_softc *sc;
sc = device_get_softc(dev);
if (bus_alloc_resources(dev, qcom_gcc_spec, &sc->res) != 0) {
device_printf(dev, "cannot allocate resources for device\n");
return (ENXIO);
}
/*
* Enable debug unit.
* This is required for Coresight operation.
* This also enables USB clock branch.
*/
qcom_qdss_enable(sc);
return (0);
}
static device_method_t qcom_gcc_methods[] = {
/* Device interface */
DEVMETHOD(device_probe, qcom_gcc_probe),
DEVMETHOD(device_attach, qcom_gcc_attach),
DEVMETHOD_END
};
static driver_t qcom_gcc_driver = {
"qcom_gcc",
qcom_gcc_methods,
sizeof(struct qcom_gcc_softc),
};
static devclass_t qcom_gcc_devclass;
EARLY_DRIVER_MODULE(qcom_gcc, simplebus, qcom_gcc_driver, qcom_gcc_devclass,
0, 0, BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
MODULE_VERSION(qcom_gcc, 1);